From a749d13acd8e079ed4c77a9456d842dc94af8f17 Mon Sep 17 00:00:00 2001 From: Josh Wu Date: Tue, 5 Nov 2013 17:59:07 +0800 Subject: mtd: atmel_nand: fix bug driver will in a dead lock if no nand detected In the atmel driver probe function, the code shows like following: atmel_nand_probe(...) { ... err_nand_ioremap: platform_driver_unregister(&atmel_nand_nfc_driver); return res; } If no nand flash detected, the driver probe function will goto err_nand_ioremap label. Then platform_driver_unregister() will be called. It will get the lock of atmel_nand device since it is parent of nfc_device. The problem is the lock is already hold by atmel_nand_probe itself. So system will be in a dead lock. This patch just simply removed to platform_driver_unregister() call. When atmel_nand driver is quit the platform_driver_unregister() will be called in atmel_nand_remove(). [Brian: the NAND platform probe really has no business registering/unregistering another driver; this fixes the deadlock, but we should follow up the likely racy behavior here with a better architecture] Signed-off-by: Josh Wu Cc: # 3.12 Signed-off-by: Brian Norris diff --git a/drivers/mtd/nand/atmel_nand.c b/drivers/mtd/nand/atmel_nand.c index ef9c9f5..469d4e2 100644 --- a/drivers/mtd/nand/atmel_nand.c +++ b/drivers/mtd/nand/atmel_nand.c @@ -2142,7 +2142,6 @@ err_no_card: if (host->dma_chan) dma_release_channel(host->dma_chan); err_nand_ioremap: - platform_driver_unregister(&atmel_nand_nfc_driver); return res; } -- cgit v0.10.2